Carbaldehydes cyclohexene

AI3-21661 BRN 0774001 3-Cyclohexene-1-carbox-aldehyde Cyclohex-3-ene-1-carbaldehyde Cyclohexene-4-carboxaldehyde A -Tetrahydrobenzaldehyde EINECS 202-858-3 HSDB 5334 NSC 16241 UN2498. Liquid mp = 1 bp = 105° = 0.9692 slightly... 

A recent example where Co2(CO)8 serves as a precatalyst is in the preparation of linear and branched aldehydes via propylene hydroformylation in supercritical C02 (93-186 bar 66-108 °C). Cyclohexane carbaldehyde is produced from cyclohexene using Co2(CO)8 and an acid RCOOH, or else is successful with another established Co catalyst, Co(OOCR)2, assumed to form in situ in the former case. Oligomerization of aldehydes such as n-butanal is achieved with Co2(CO)6L2 as catalyst (L = CO, PR3).1364... 

Fig. 3.1. (cont.) (S)(+)-isopiperitenone (3-methyl-6-(5 )-isopropenyl-2-cyclo-hexen-l-one) 17, isopiperitenol (3-methyl-6-isopropenyl-2-cyclohexen-l-ol) 18, isorobinal (4-isopropenyl-3-oxo-l-cyclohexene-1-carbaldehyde) 19, robi-nal (3-oxo-4-isopropylidene-l-cyclohexene-1-carbaldehyde) 20, a, a -acariolide (3-(4/-methyl-3/-pentenyl)-2(5//)-furanone) 21, a,/ -acariolide (4-(4 -methyl-3 -pentenyl)-2(57/)-furanone) 22, / -acariolide (( )-2-(4/-methyl-3/-pentenylidene)-... 

Acetophenone-sensitized photolysis of l-methyl-3-phenyl-2-cyclohexene-carbaldehyde oxime acetate (56) A solution of 56 (298 mg, 1.16 mmol)... 

This catalytic cascade was first realized using propanal, nitrostyrene and cinnamaldehyde in the presence of catalytic amounts of (9TMS-protected diphenylprolinol ((.S )-71,20 mol%), which is capable of catalyzing each step of this triple cascade. In the first step, the catalyst (S)-71 activates component A by enamine formation, which then selectively adds to the nitroalkene B in a Michael-type reaction (Hayashi et al. 2005). The following hydrolysis liberates the catalyst, which is now able to form the iminium ion of the a, 3-unsaturated aldehyde C to accomplish in the second step the conjugate addition of the nitroalkane (Prieto et al. 2005). In the subsequent third step, a further enamine reactivity of the proposed intermediate leads to an intramolecular aldol condensation. Hydrolysis returns the catalyst for further cycles and releases the desired tetrasubstituted cyclohexene carbaldehyde 72 (Fig. 8) (Enders and Hiittl 2006). 

The fact that the residues R -R3 of the precursors A, B and C can be broadly varied demonstrates the high flexibility of our approach. R1 of component A can bear simple to demanding residues as well as valuable functional groups (Scheme 17). R2 is limited to aromatic and heteroaromatic substituents, due to the lower reactivity of the aliphatic ni-troalkenes. The residue R3 of component C allows the broadest diversity. Aliphatic as well as aromatic moieties are tolerated. Furthermore, acrolein (R3 = H) can be used, affording trisubstituted cyclohexene carbaldehydes. The best yields were obtained with aromatic substituents R2 and R3 (38%-60%). The replacement of R3 by aliphatic residues led to lower yields (25% and 29%), whereas sterically demanding aldehydes A had less influence on the yield. In contrast, the variation of the residues had only a small impact on the diastereoselectivity (68 32-... 

The process mechanism as shown in Figure 2.23 consists of an initial activation of the aldehyde (66) by the catalyst [(5)-67] with the formation of the corresponding chiral enamine, which then, selectively, adds to nitroalkene (65) in a Michael-type reaction. The following hydrolysis liberates the catalyst, which forms the iminium ion of the a,(3-unsaturated aldehyde (62) to accomplish the conjugate addition with the nitroalkane A. In the third step, another enamine activation of the intermediate B leads to an intramolecular aldol condensation via C. Finally, the hydrolysis of it returns the catalyst and releases the desired chiral tetra-substituted cyclohexene carbaldehyde (68). 

The synthetic applications of benzothiazoles appeared to be limited by the fact that the thiazole ring cannot be hydrolytically cleaved. However, this problem was solved by quatemization followed by reduction with NaBH4 to produce 3-methyl-2,3-dihydrobenzothiazole, as shown in the synthesis of cyclohexene-1-carbaldehyde [104] ... 

Methyl-3-pentenyl)-3-cyclohexene-1-carbaldehyde + 4-(4-methyl-3-pentenyl)-3-cyclohexene-1-carbaldehyde. 

Dimethyl-3-cyclohexen-1 -carbaldehyde 2,4-Dimethyl-3-cyclohexene carbaldehyde 2,4-Dimethylcyclohex-3-ene-1 -carbaldehyde. See... 

Dimethyl-3-cyclohexene-1-carbaldehyde CAS 67801-65-4 EINECS/ELINCS 267-186-5 Synonyms 3,6-Dimethylcyclohex-3-ene-1 -... 

Manuf/Distrib. Lothar Streeck http //www.lothar-streeck. de Dimethyl-3-cyclohexene carboxaldehyde CAS 68737-61-1 EINECS/ELINCS 272-113-5 Synonyms Dimethylcyclohex-3-ene-1 -carbaldehyde ... 

Dimethylbicyclo [3.2.1] octan-8-one oxime Dimethyl-3-butenyl isobutyrate 3,5-Dimethyl-3-cyclohexene-1-carbaldehyde 3,6-Dimethyl-3-cyclohexene-1-carbaldehyde 2,4-Dimethyl-3-cyclohexene carboxaldehyde... 

Dimethyl-3-cyclohexene-1-carbaldehyde Dimethylcyclohexyl methyl ketone 4,8-Dimethyl-4,9-decadienal 5,9-Dimethyl-4,8-decadienal 1,3-Dimethyl-3-phenylbutylacetate Ethyl o-anisate Geranyl nitrile Hexadienyl isobutyrate Hexahydrohexamethyl cyclopentabenzopyran Hydroxycitronellal dimethyl acetal... 

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